US20170369524A1 - In-situ Solvent Recycling Process for Solid Phase Peptide Synthesis at Elevated Temperatures - Google Patents

In-situ Solvent Recycling Process for Solid Phase Peptide Synthesis at Elevated Temperatures Download PDF

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US20170369524A1
US20170369524A1 US15/490,090 US201715490090A US2017369524A1 US 20170369524 A1 US20170369524 A1 US 20170369524A1 US 201715490090 A US201715490090 A US 201715490090A US 2017369524 A1 US2017369524 A1 US 2017369524A1
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deprotection
coupling
solid phase
cycle
phase peptide
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Jonathan M. Collins
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CEM Corp
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Priority to CA3034810A priority patent/CA3034810C/en
Priority to EP17847113.2A priority patent/EP3507299B1/en
Priority to DK17847113.2T priority patent/DK3507299T3/en
Priority to PCT/US2017/028254 priority patent/WO2018044356A1/en
Priority to JP2019511957A priority patent/JP2019530659A/en
Priority to CN201780053940.9A priority patent/CN109715647A/en
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K1/00—General methods for the preparation of peptides, i.e. processes for the organic chemical preparation of peptides or proteins of any length
    • C07K1/04—General methods for the preparation of peptides, i.e. processes for the organic chemical preparation of peptides or proteins of any length on carriers
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K1/00—General methods for the preparation of peptides, i.e. processes for the organic chemical preparation of peptides or proteins of any length
    • C07K1/04—General methods for the preparation of peptides, i.e. processes for the organic chemical preparation of peptides or proteins of any length on carriers
    • C07K1/045—General methods for the preparation of peptides, i.e. processes for the organic chemical preparation of peptides or proteins of any length on carriers using devices to improve synthesis, e.g. reactors, special vessels

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  • the invention is a method of deprotection in solid phase peptide synthesis in which the improvement comprises adding the deprotection composition in high concentration and small volume to the mixture of the coupling solution, the growing peptide chain, and any excess activated amino acid from the preceding coupling cycle; and without any draining step between the coupling step of the previous cycle and the addition of the deprotection composition for the successive cycle; and with the coupling solution at least 30° C.
  • the invention is a method of deprotection in solid phase peptide synthesis in which the improvement comprises adding the deprotection composition in high concentration and small volume to the mixture of the coupling solution, the growing peptide chain, and any excess activated amino acid from the preceding coupling cycle; and without any draining step between the coupling step of the previous cycle and the addition of the deprotection composition for the successive cycle which removes at least 50% of the volume of the previous cycle coupling solution; and with the coupling solution at a temperature of at least 30° C.
  • FIG. 1 illustrates a traditional SPPS Cycle
  • FIG. 2 illustrates more recent SPPS Cycles for High Efficiency Solid Phase Peptide Synthesis (HE-SPPS)
  • FIG. 3 illustrates in-situ solvent recycling process for solid phase peptide synthesis.
  • This invention presents a novel process whereby the coupling and deprotection steps occur within the same solvent.
  • concentrated base is added directly to the resin coupling solution after a desired period of time for the coupling to occur.
  • the deprotection step is then immediately started when the base is added. Therefore, the onset of the deprotection step is immediately after the coupling step without any time delay.
  • peptides were synthesized using a LIBERTY BLUETM PRIMETM system (CEM Corp., Matthews, N.C., USA) allowing for automated in-situ solvent recycling and evaporation based washing.
  • the peptides were synthesized at 0.05 mmol scale with 10 equivalents of amino acid using CarboMAXTM coupling with amino acid/carbodiimide/ethyl 2-cyano-2-(hydroxyimino)acetate (AA/DIC/Oxyma) (1:2:1) based activation for 100 sec at 90° C. (E. Atherton, N. L. Benoiton, E. Brown, R. Sheppard and B. J.
  • This new process provided a significant reduction in standard cycle time (2 minutes 57 seconds) from (a)—elimination of the coupling drain time, (b)—elimination of the deprotection delivery time between steps, and (c)—elimination of the temperature ramp time for the deprotection step thereby allowing a shorter deprotection time to be used. Additionally, significant solvent savings were possible with the complete elimination of the deprotection solvent during each cycle.

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  • General Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
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Abstract

An improvement in of deprotection in solid phase peptide synthesis is disclosed. The method includes the steps of adding the deprotection composition in high concentration and small volume to the mixture of the coupling solution, the growing peptide chain, and any excess activated amino acid from the preceding coupling cycle; and without any draining step between the coupling step of the previous cycle and the addition of the deprotection composition for the successive cycle; and with the coupling solution at a temperature of at least 30° C.

Description

    RELATED APPLICATIONS
  • This application is a continuation in part of Ser. No. 1,5299,931, filed Oct. 21, 2016, for “Improvements in Solid Phase Peptide Synthesis.”
    • BACKGROUND
  • Bruce Merrifield's pioneering development of solid phase peptide synthesis created a useful process for synthesis peptide chains through its use of filtration to remove reagents between steps. The process has involved repetitive cycles which include coupling and deprotection with washing and filtration in-between each step (FIG. 1). It has commonly been assumed that washing is required between each step to completely remove the reagents previously used so that they don't undesirably participate in the next step. This typically involves “insertions” which refer to the incorporation of an extra amino acid. This is thought to occur through either residual base removing the protecting group (Fmoc) on an amino acid recently coupled thereby allowing a second amino acid to “insert”; or through residual activated amino acid left behind during the subsequent deprotection step which could couple to deblocked sites thereby “inserting” an extra amino acid from the previous step. It was recently shown, however, that washing after the coupling step was not required for the successful synthesis of peptides. In this work the coupling step was drained and the deprotection solution was subsequently added to the vessel (J. Collins, K. Porter, S. Singh and G. Vanier, “High-Efficiency Solid Phase Peptide Synthesis (HE-SPPS),” Org. Lett., vol. 16, pp. 940-943, 2014) (FIG. 2).
    • SUMMARY
  • The invention is a method of deprotection in solid phase peptide synthesis in which the improvement comprises adding the deprotection composition in high concentration and small volume to the mixture of the coupling solution, the growing peptide chain, and any excess activated amino acid from the preceding coupling cycle; and without any draining step between the coupling step of the previous cycle and the addition of the deprotection composition for the successive cycle; and with the coupling solution at least 30° C.
  • In another aspect the invention is a method of deprotection in solid phase peptide synthesis in which the improvement comprises adding the deprotection composition in high concentration and small volume to the mixture of the coupling solution, the growing peptide chain, and any excess activated amino acid from the preceding coupling cycle; and without any draining step between the coupling step of the previous cycle and the addition of the deprotection composition for the successive cycle which removes at least 50% of the volume of the previous cycle coupling solution; and with the coupling solution at a temperature of at least 30° C.
  • The foregoing and other objects and advantages of the invention and the manner in which the same are accomplished will become clearer based on the followed detailed description taken in conjunction with the accompanying drawings.
    • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 illustrates a traditional SPPS Cycle
  • FIG. 2 illustrates more recent SPPS Cycles for High Efficiency Solid Phase Peptide Synthesis (HE-SPPS)
  • FIG. 3 illustrates in-situ solvent recycling process for solid phase peptide synthesis.
    •  DETAILED DESCRIPTION
  • This invention presents a novel process whereby the coupling and deprotection steps occur within the same solvent. In this process concentrated base is added directly to the resin coupling solution after a desired period of time for the coupling to occur. The deprotection step is then immediately started when the base is added. Therefore, the onset of the deprotection step is immediately after the coupling step without any time delay.
  • Additionally, only a small volume of base is required since it can use the solvent present from the coupling reaction. This requires a sophisticated reagent delivery system for the base that is accurate at very small volumes (0.5 mL) with rapid delivery. Typically, a 20% solution of base (piperidine) in solvent is used for the deprotection step. Excess base concentration can increase base-catalyzed side reactions and therefore significant solvent is required. This means that significant solvent can be saved from this process by adding concentrated base to the coupling solvent.
  • To demonstrate the effectiveness of this new process a batch of 24 peptides were assembled using an automated peptide synthesizer modified to perform the in-situ solvent recycling step during each cycle.
  • Materials and methods:
  • All peptides were synthesized using a LIBERTY BLUE™ PRIME™ system (CEM Corp., Matthews, N.C., USA) allowing for automated in-situ solvent recycling and evaporation based washing. The peptides were synthesized at 0.05 mmol scale with 10 equivalents of amino acid using CarboMAX™ coupling with amino acid/carbodiimide/ethyl 2-cyano-2-(hydroxyimino)acetate (AA/DIC/Oxyma) (1:2:1) based activation for 100 sec at 90° C. (E. Atherton, N. L. Benoiton, E. Brown, R. Sheppard and B. J. Williams, “Racemization of Activated, Urethane-protected Amino-acids by p-Dimethylaminopyridine. Significance in Solid Phase Peptide Synthesis,” J.C.S. Chem. Comm., pp. 336-337, 1981). ProTide resins (CEM Corp.) based on TentaGel® technology were used for synthesis with either a Rink Amide linker or a Cl-TCP(Cl) linker with unactivated loading of the first amino acid with DIEA at 90° C. for 5 min. The deprotection step was performed for 50 sec at 95° C. and initiated by adding 0.5mL of 50% pyrrolidine directly to the coupling solution. A single 1×4 mL wash was used in between the deprotection and coupling steps. Peptides were cleaved with Trifluoroacetic acid (TFA)/triisopropylsilane/water/2,2′-(ethylenedioxy)diethanethiol (TFA/TIS/H2O/DODt) (92.5:2.5:2.5:2.5) for 30 min at 38° C. using a RAZOR™ cleavage system (CEM Corp.).
  • Figure US20170369524A1-20171228-C00001
  • Results and discussion:
  • TABLE 1
    Automated Sequential Batch Synthesis of 24 Peptides
    Resin UPLC Synthesis
    # Peptide Disease Area Used Purity Time
     1 GRP Regulates RA 81 1:22
    VPLPAGGGTVLTKMYPRGNHWAVGHLM-NH2 Gastrin Release ProTide
     2 Glucagon Hypoglycemia RA 75 1:28
    H-HSQGTFTSDYSKYLDSRRAQDFVQWLMNT-NH2 ProTide
     3 Bivalirudin Blood thinner Cl-2-Cl- 71 1:05
    H-fPRPGGGGNGDFEEIPEEYL-OH Trt
     4 Angiotensin Vasoconstrictor Cl-2-Cl- 82 0:30
    H-NRVYVHPF-OH Trt
     5 PTH 1-34 Osteoporosis RA 70 1:43
    H-SVSEIQLMHNLGKHLNSMERVEWLRKKLQDVHNF- ProTide
    NH2
     
     6 Gonadorelin Fertility RA 91 0:35
    pEHWSYGLRPG-NH2 ProTide
     7 Triptorelin Breast Cancer, RA 73 0:35
    pEHWSYwLRPG-NH2 Prostrate ProTide
    Cancer,
     8 Liraglutide Diabetes RA 80 1:31
    H-HAEGTFTSDVSSYLEGQAAK(Y-E- ProTide
    palmitoyl)EFIAWLVRGRG-NH2
     9 Exenatide Diabetes RA 74 1:58
    H- ProTide
    HGEGTFTSDLSKQMEEEAVRLFIEWLKNGGPSSGAPPPS-
    NH2
    10 MOG (35-55) Multiple RA 71 1:05
    H-MEVGWYRSPFSRVVHLYRNGK-NH2 Sclerosis ProTide
    11 Secretin Osmoregulation RA 70 1:19
    H-HDGTFTSELSRLRDSARLQRLLQGLV-NH2 ProTide
    12 Teriparatide Osteoporosis RA 60 1:43
    H-SVSEIQLMHNLGKHLNSMERVEWLRKKLQDVHNF- ProTide
    NH2
    13 GLP-1 (7-37) Diabetes RA 74 1:34
    H-HAEGTFTSDVSSYLEGQAAKEFIAWLVKGRG-NH2 ProTide
    14 Magainin 1 Antibiotic RA 79 1:11
    H-GIGKFLHSAGKFGKAFVGEIMKS-NH2 ProTide
    15 Tetracosactide Adrenal Cortex RA 77 1:13
    H-SYSMEHFRWGKPVGKKRRPVKVYP-NH2 stimulant ProTide
    16 [Arg8]-Vasopressin Hormone (blood RA 94 0:32
    H-CYFQNCPRG-NH2 vessel ProTide
    17 Ubiquitin Protein RA ≧60 3:44
    MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQ signaling agent ProTide
    18 Parasin I Antibiotic RA 87 0:59
    H-KGRGKQGGKVRAKAKTRSS-NH2 ProTide
    19 Dynorphin A Opioid RA 71 0:53
    H-YGGFLRRIRPKLKWDNQ-NH2 Research ProTide
    20 ACP Fatty Acid RA 92 0:32
    H-VQAAIDYING-NH2 Synthesis ProTide
    21 BAM 3200 Opioid RA 70 1:16
    H-YGGFMRRVGRPEWWMDYQKRYGGFL-NH2 Research ProTide
    22 HIV-TAT  (47-57) HIV/AIDS RA 93 0:31
    Fmoc-YGRKKRRQRRR-NH2 Research ProTide
    23 HIV-TAT (48-60) HIV/AIDS RA 88 0:39
    Fmoc-GRKKRRQRRRPPQ-NH2 Research ProTide
    24 Pramlintide Diabetes RA 72 1:52
    KCNTATCATQRLANFLVHSSNNFGPILPPTNVGSNTY-- ProTide
  • All peptides synthesized in Table 1 gave the desired target as the major peak with a standard cycle time of 2 minutes and 58 seconds. The in-situ solvent recycling process allowed for 0.5mL of a concentrated pyrrolidine (BP 87° C.) solution to be added to the end of the coupling step (without draining). An advantage of this setup was that the deprotection immediately proceeded very close to the desired temperature (95° C.) because the coupling solution was already at 90° C. During the deprotection process a vacuum was applied and the pyrrolidine was evaporated and subsequently condensed in the waste container. This allowed only a single wash step (1×4 mL) to be required at the end of the deprotection step.
  • Total synthesis time for entire batch: 32.6 hours
  • This new process provided a significant reduction in standard cycle time (2 minutes 57 seconds) from (a)—elimination of the coupling drain time, (b)—elimination of the deprotection delivery time between steps, and (c)—elimination of the temperature ramp time for the deprotection step thereby allowing a shorter deprotection time to be used. Additionally, significant solvent savings were possible with the complete elimination of the deprotection solvent during each cycle.
  • In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms have been employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

Claims (10)

1. A method of deprotection in solid phase peptide synthesis in which the improvement comprises:
adding the deprotection composition in high concentration and small volume to the mixture of the coupling solution, the growing peptide chain, and any excess activated amino acid from the preceding coupling cycle; and
without any draining step between the coupling step of the previous cycle and the addition of the deprotection composition for the successive cycle; and
with the coupling solution at least 30° C.
2. A method according to claim 1 wherein the deprotection composition is an organic base
3. A method according to claim 1 using Fmoc solid phase peptide chemistry
4. A method according to claim 2 with the deprotection solution having a concentration of organic base of at least 50% by volume
5. A method according to claim 1 where the deprotection composition is added in an amount that is less than ⅓ of the volume of the coupling solution.
6. A method of deprotection in solid phase peptide synthesis in which the improvement comprises:
adding the deprotection composition in high concentration and small volume to the mixture of the coupling solution, the growing peptide chain, and any excess activated amino acid from the preceding coupling cycle; and
without any draining step between the coupling step of the previous cycle and the addition of the deprotection composition for the successive cycle which removes at least 50% of the volume of the previous cycle coupling solution; and
with the coupling solution at a temperature of at least 30° C.
7. A method according to claim 6 wherein the deprotection composition is an organic base.
8. A method according to claim 6 using Fmoc solid phase peptide chemistry.
9. A method according to claim 6 with the deprotection solution concentration at least 50% by volume.
10. A method according to claim 6 where the deprotection composition is added in an amount that is less than ⅓ the volume of the coupling solution.
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US15/490,090 US10239914B2 (en) 2015-10-23 2017-04-18 In-situ solvent recycling process for solid phase peptide synthesis at elevated temperatures
PCT/US2017/028254 WO2018044356A1 (en) 2016-09-03 2017-04-19 In-situ solvent recycling process for solid phase peptide synthesis at elevated temperatures
EP17847113.2A EP3507299B1 (en) 2016-09-03 2017-04-19 In-situ solvent recycling process for solid phase peptide synthesis at elevated temperatures
DK17847113.2T DK3507299T3 (en) 2016-09-03 2017-04-19 PROCEDURE FOR IN-SITU SOLVENT RECOVERY FOR SOLID-PHASE PEPTIDE SYNTHESIS AT ELEVATED TEMPERATURES
CA3034810A CA3034810C (en) 2016-09-03 2017-04-19 In-situ solvent recycling process for solid phase peptide synthesis at elevated temperatures
JP2019511957A JP2019530659A (en) 2016-09-03 2017-04-19 In-situ solvent recycling method for solid phase peptide synthesis at high temperature
CN201780053940.9A CN109715647A (en) 2016-09-03 2017-04-19 Situ solvent recovery method for high temperature solid-state peptide synthesis

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PCT/US2016/058181 WO2017070512A1 (en) 2015-10-23 2016-10-21 Improvements in solid phase peptide synthesis
WOPCTUS2016058181 2016-10-21
WOPCT/US2016/058181 2016-10-21
US15/299,931 US10125163B2 (en) 2015-10-23 2016-10-21 Solid phase peptide synthesis
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US6084226A (en) 1998-04-21 2000-07-04 Cem Corporation Use of continuously variable power in microwave assisted chemistry
US20040238794A1 (en) 2003-05-30 2004-12-02 Karandikar Prashant G. Microwave processing of composite bodies made by an infiltration route
US7393920B2 (en) 2003-06-23 2008-07-01 Cem Corporation Microwave-assisted peptide synthesis
WO2006026184A2 (en) * 2004-08-20 2006-03-09 Washington University Blood brain barrier permeation peptides
US8314208B2 (en) 2006-02-10 2012-11-20 Cem Corporation Microwave enhanced N-fmoc deprotection in peptide synthesis
WO2012024224A1 (en) 2010-08-16 2012-02-23 Cem Corporation Water soluble solid phase peptide synthesis
US8906681B2 (en) * 2011-08-02 2014-12-09 The Scripps Research Institute Reliable stabilization of N-linked polypeptide native states with enhanced aromatic sequons located in polypeptide tight turns
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